/*
*球形滚动代码是从网上找来的
*/
(function($){
	$.fn.tagCloud = function(){
		var length = $(this).length;
		for(var i=0; i<length;i++){
			action($(this).get(i));	
		}
		return $(this);
		function action(oDiv){		
				var radius = 180;
				var dtr = Math.PI/180;
				var d=1200;

				var mcList = [];
				var active = false;
				var lasta = 1;
				var lastb = 1;
				var distr = true;
				var tspeed=5;
				var size=250;

				var mouseX=0;
				var mouseY=0;

				var howElliptical=1;

				var aA=null;
				
					var i=0;
					var oTag=null;
					
					aA=oDiv.getElementsByTagName('li');
					
					for(i=0;i<aA.length;i++)
					{
						oTag={};
						
						oTag.offsetWidth=aA[i].offsetWidth;
						oTag.offsetHeight=aA[i].offsetHeight;
						
						mcList.push(oTag);
					}
					
					sineCosine( 0,0,0 );
					
					positionAll();
					
					oDiv.onmouseover=function ()
					{
						active=false;
					};
					
					oDiv.onmouseout=function ()
					{
						active=true;
					};
					
					oDiv.onmousemove=function (ev)
					{
						var oEvent=window.event || ev;
						
						mouseX=oEvent.clientX-(oDiv.offsetLeft+oDiv.offsetWidth/2);
						mouseY=oEvent.clientY-(oDiv.offsetTop+oDiv.offsetHeight/2);
						
						mouseX/=5;
						mouseY/=5;
					};
					
					setInterval(update, 50);
				
		
				function update()
				{
					var a;
					var b;
					
					if(active)
					{
						a = (-Math.min( Math.max( -mouseY, -size ), size ) / radius ) * tspeed;
						b = (Math.min( Math.max( -mouseX, -size ), size ) / radius ) * tspeed;
					}
					else
					{
						a = lasta * 0.98;
						b = lastb * 0.98;
					}
					
					lasta=a;
					lastb=b;
					
					if(Math.abs(a)<=0.01 && Math.abs(b)<=0.01)
					{
						return;
					}
					
					var c=0;
					sineCosine(a,b,c);
					for(var j=0;j<mcList.length;j++)
					{
						var rx1=mcList[j].cx;
						var ry1=mcList[j].cy*ca+mcList[j].cz*(-sa);
						var rz1=mcList[j].cy*sa+mcList[j].cz*ca;
						
						var rx2=rx1*cb+rz1*sb;
						var ry2=ry1;
						var rz2=rx1*(-sb)+rz1*cb;
						
						var rx3=rx2*cc+ry2*(-sc);
						var ry3=rx2*sc+ry2*cc;
						var rz3=rz2;
						
						mcList[j].cx=rx3;
						mcList[j].cy=ry3;
						mcList[j].cz=rz3;
						
						per=d/(d+rz3);
						
						mcList[j].x=(howElliptical*rx3*per)-(howElliptical*2);
						mcList[j].y=ry3*per;
						mcList[j].scale=per;
						mcList[j].alpha=per;
						
						mcList[j].alpha=(mcList[j].alpha-0.6)*(10/6);
					}
					
					doPosition();
					depthSort();
				}

				function depthSort()
				{
					var i=0;
					var aTmp=[];
					
					for(i=0;i<aA.length;i++)
					{
						aTmp.push(aA[i]);
					}
					
					aTmp.sort
					(
						function (vItem1, vItem2)
						{
							if(vItem1.cz>vItem2.cz)
							{
								return -1;
							}
							else if(vItem1.cz<vItem2.cz)
							{
								return 1;
							}
							else
							{
								return 0;
							}
						}
					);
					
					for(i=0;i<aTmp.length;i++)
					{
						aTmp[i].style.zIndex=i;
					}
				}

				function positionAll()
				{
					var phi=0;
					var theta=0;
					var max=mcList.length;
					var i=0;
					
					var aTmp=[];
					var oFragment=document.createDocumentFragment();
					
					//随机排序
					for(i=0;i<aA.length;i++)
					{
						aTmp.push(aA[i]);
					}
					
					aTmp.sort
					(
						function ()
						{
							return Math.random()<0.5?1:-1;
						}
					);
					
					for(i=0;i<aTmp.length;i++)
					{
						oFragment.appendChild(aTmp[i]);
					}
					
					oDiv.appendChild(oFragment);
					
					for( var i=1; i<max+1; i++){
						if( distr )
						{
							phi = Math.acos(-1+(2*i-1)/max);
							theta = Math.sqrt(max*Math.PI)*phi;
						}
						else
						{
							phi = Math.random()*(Math.PI);
							theta = Math.random()*(2*Math.PI);
						}
						//坐标变换
						mcList[i-1].cx = radius * Math.cos(theta)*Math.sin(phi);
						mcList[i-1].cy = radius * Math.sin(theta)*Math.sin(phi);
						mcList[i-1].cz = radius * Math.cos(phi);
						
						aA[i-1].style.left=mcList[i-1].cx+oDiv.offsetWidth/2-mcList[i-1].offsetWidth/2+'px';
						aA[i-1].style.top=mcList[i-1].cy+oDiv.offsetHeight/2-mcList[i-1].offsetHeight/2+'px';
					}
				}

				function doPosition()
				{
					var l=oDiv.offsetWidth/2;
					var t=oDiv.offsetHeight/2;
					for(var i=0;i<mcList.length;i++)
					{
						aA[i].style.left=mcList[i].cx+l-mcList[i].offsetWidth/2+'px';
						aA[i].style.top=mcList[i].cy+t-mcList[i].offsetHeight/2+'px';
						
						aA[i].style.fontSize=Math.ceil(12*mcList[i].scale/2)+8+'px';
						
						aA[i].style.filter="alpha(opacity="+100*mcList[i].alpha+")";
						aA[i].style.opacity=mcList[i].alpha;
					}
				}

				function sineCosine( a, b, c)
				{
					sa = Math.sin(a * dtr);
					ca = Math.cos(a * dtr);
					sb = Math.sin(b * dtr);
					cb = Math.cos(b * dtr);
					sc = Math.sin(c * dtr);
					cc = Math.cos(c * dtr);
				}
		}
	}
})($);